


World Mother

by GrandLeviathan



Category: Fate/Grand Order
Genre: Blow Jobs, Consensual Sex, Creampie, F/M, First Time, Fluff, Fluff and Smut, Foreplay, Kissing, Prompt Fic, Romance, Smut, Vaginal Sex, naked apron
Language: English
Status: Completed
Published: 2019-12-22
Updated: 2019-12-22
Packaged: 2021-02-24 16:48:04
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,421
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21901231
Author URL: https://archiveofourown.org/users/GrandLeviathan/pseuds/GrandLeviathan
Summary: One month passed since Tiamat was defeated. The cost? Lots of kisses and affection.Though Ritsuka never expected she'd pay it back, with interest.
Relationships: Fujimaru Ritsuka/Tiamat | Beast II
Comments: 14
Kudos: 87





	World Mother

**Author's Note:**

> The plot behind this was inspired by the follow pic:  
> https://danbooru.donmai.us/posts/2886615
> 
> Enjoy~

_**''RAAAARGH!''** _

_The Beast's bellowing roar echoed over the ruined battlefield, no less strong than it had been at the start of the calamitous battle – even though countless wounds marred the goddess' body._

_Dozens upon dozens of Servants had surrounded her from all sides, peppering her with ranged attacks or running up her enlarged body, hacking and slashing at whatever defences she tried to muster. No matter what she did, she was destined to lose; for these Servants had little to no connection to humanity, allowing them to harm her greatly._

_And yet amidst all the rage and chaos, amongst the Servants stood a single human – a magician. One who looked upon her with no cold determination, no disdain nor displeasure. Instead, all that shone in his eyes were quiet pity and an indecipherable softness, as if he wanted nothing more than to stop the assault he himself ordered._

_Tiamat gazed down upon the measly human, trying to raise her clawed hand to no avail – the golden chains tying it to the ground, stopping her. Yet before she could attempt to lash out at the leader, the young man spoke._

_''Enough.'' He said so softly she almost couldn't hear it, despite her supernatural hearing. ''I don't want to hurt you anymore, Tiamat-san. Surrender.''_

_In response Tiamat flared, letting out an unearthly shriek of fury at the mortal who dared to ask her to give up. Many of the Servants tensed up, yet the human seemed entirely unfazed by her stormy fury._

_Her pupils dilated, focusing intently as the human stretched out a hand towards her – the gesture completely harmless. ''I'm serious. You don't deserve this. You don't deserve to be hurt so much... please, surrender. You don't have to do this any more. You can join us; help us protect humanity as well. I know you don't like us... but, I'll prove to you that humans can love you back, just as you once loved humans.''_

_His words struck a cord within Tiamat, her rage wilting into a simmering anger. Slowly she gazed around her, only now taking note of the Servants being healed by various other Masters. She had lost. She wasn't so arrogant as to ignore that. Even if she took down a few with her, what did it matter... when she could take an alternate path?_

_And slowly, Tiamat brought her head down to the human's level – as close as she could anyway – and let out a low, rumbling growl of submission._

_Ritsuka Fujimaru smiled at her. ''I promise you Tiamat, I'll show you.''_

X-x-X

''Haah... what a pain...''

Ritsuka's low groan echoed down the halls of Chaldea, the Master stretching his arms above his head and working out the kinks. After hours of training with his Heroic Spirits it had taken a toll on him, not least because they had gotten him involved. Nothing major; just him dodging while they attacked, making sure he kept his reflexes sharp. Given his status as a Master, his primary objective was commanding, and evading enemies; leaving said enemies to his Heroic Spirits.

''You did well today, Master.'' Jeanne smiled warmly at him, gently patting his arm.

''Yeah; soon you might be able to keep up with me~'' Okita Souji cheerfully added, a skip to her step.

''How you still have energy, I'll never know...'' Ritsuka muttered dryly.

Okita merely giggled, elbowing him playfully before departing, taking a hall down to her room. Jeanne followed suit, bidding him a good rest as she went back to her own room, murmuring something about a shower. The walk back to his room from there was in silence, the distant murmurings of other Heroic Spirits fluttering from further down the halls.

It had been over a month now since the grand cataclysm of a battle against Tiamat, and since she had 'defected' to their side. At first her presence was looked upon with suspicion, but through his efforts she was gradually assimilated into the culture at Chaldea – after all, every Spirit here came from different, unique backgrounds; it was only natural that even a Beast could find friends here. Though given her unique nature, Olga had opted to have her stay with him; often referring to him as her 'handler'.

While he disliked such a condescending title, he understood the general fear the higher-ups had – after all, Tiamat was undeniably one of the strongest beings in existence, at least in Chaldea. She was virtually immune to anything with a connection to humanity, sharply narrowing down the list of available Heroic Spirits who could reasonably fight her. So to those who didn't know her, Tiamat was just a dangerous beast, one held on a leash by Ritsuka alone.

Shaking off his lingering thoughts as he reached his room, Ritsuka fumbled for his key before unlocking it, stepping inside. ''Tiamat-san, I'm back.''

''Aaah~'' Came a deep, happy groan from the attached kitchenette.

Ritsuka closed the door behind him, glancing over in her direction... and immediately blushed a rosy red as he found Tiamat standing by the oven, wearing nothing but a pink apron. Her back was to him, giving him a good view of her curvy rear before she turned to face him; fixing him with a warm, affectionate smile. Even then the sides of her large breasts and wide hips peeked out from the sides of her apron, said apron only coming down to her thighs and leaving her smooth legs exposed.

''Tiamat-san?'' Ritsuka asked in confusion. While her state of dress wasn't a complete surprise – she liked to sit around in just panties and one of his shirts – but this was a step further than normal.

The goddess approached him and wrapped her arms around him, pulling him into a hug that resulted in her heavenly-soft breasts squishing against his chest, her apron thin enough that he could feel her nipples through the fabric. His blush deepened and he returned the hug, letting it last for a few seconds before pulling back.

Before he could ask why she was in such little clothing she cupped his cheeks and pulled him into a deep kiss, her wonderfully-soft lips meshing against his. With a bright blush he returned the kiss, privately savouring the pleasant sensation. His theory was that she treated kisses as a sign of love, and since he promised to 'show' her humanity's love, this was her interpretation of it. He didn't mind though... not in the least.

After a long moment Tiamat pulled back from the kiss, smiling happily at him. While the goddess couldn't communicate in human language, she made up for it with physically emoting what she meant and through her incoherent, yet expressive groans and moans.

''Aah.'' Tiamat groaned warmly, tugging on his hand.

Curious and still blushing Ritsuka let her lead him over to the kitchen, his eyes landing on a modest sponge cake. With a glint of warm eagerness Tiamat found a knife and cut a slice from it, offering it to him with a look of eager anticipation. Smiling embarrassedly Ritsuka took the offered cake and took a bite, finding it to be cinnamon-flavoured.

''It's good.'' He complimented, making Tiamat's face light up. ''You're getting better by the day, haha...''

Tiamat groaned happily in response, cutting herself a slice and nibbling on it too. He had introduced Tiamat to baking in an attempt to help distract her – being cooped up in his room for most of the day wasn't the most thrilling activity, especially for a goddess born from primordial chaos, and she wasn't overly keen on exploring Chaldea on her own. With surprising eagerness she had taken to baking him food whenever he returned, not unlike a loving housewife.

Mentally dismissing the embarrassing thought Ritsuka went over to his closet, finishing off his cake before acquiring a fresh uniform. It was still late afternoon and he was all hot from having dodged a bunch of spells and attacks, so a shower sounded good about now.

Just as he was about to head off to the bathroom, however, he was startled to feel a pair of arms wrapping around him – followed by a pair of large, soft breasts pressing against his back. Ritsuka blushed at the contact, his cheeks brightening when he felt her breath brush against his neck.

''Aaah~'' Tiamat groaned softly, nuzzling against him.

Ritsuka squirmed in her grip until he could turn around to face her, having to tilt his head up to face her. Even with how tall he was she still stood a little bit taller, gazing down at him with open affection. Before he could voice his curiosity she leaned in and kissed him, this time deeper than the first time. He grunted in surprise and hesitantly returned the kiss, shivering when one of her hands sneaked up and into his hair, deepening the kiss further.

After a long few seconds Tiamat broke off the kiss, nuzzling her cheek against his. Ritsuka flushed at the open affection, his hands settling on her naked hips on reflex – a shiver running up his spine as he felt how soft her hips were. Every part of her felt so invitingly soft and warm, and dimly he wondered if her pillowy breasts would feel even softer.

''Tiamat-san?'' Ritsuka spoke in confusion.

Tiamat smiled lovingly at him, her hands sliding down and laying them over his, guiding them further down. His eyes widened a fraction but Tiamat captured his lips before he could speak, muffling his surprised groan and happily kissing him. Hesitantly Ritsuka let Tiamat guide his hands down to her ass, tenderly giving her ass a grope – eliciting a pleased moan from Tiamat.

He blushed at the strangely-erotic sound, breaking off from the kiss for air. Just as he caught his breath Tiamat kissed him again, groaning lovingly into his mouth. He quickly found himself liking the sound, willingly deepening the kiss and slowly pushing back against her, causing Tiamat to slowly walk backwards – until her legs hit the bed, and she fell back with a wordless yelp.

Ritsuka fell with her, landing atop her – catching himself on his arms. For a long moment the only sound in the bedroom was their breathing, a thin strand of light-blue hair dangling over her right eye before he slowly brushed it aside. Her crimson gaze was locked solely onto his, a cute little smile playing at her lips the whole time; as if just staring at him brought her happiness.

''You're awfully affectionate today...'' Ritsuka breathed softly.

''Aah.'' Tiamat groaned quietly, her hands sliding up and cupping his cheeks.

Once more the chaos goddess pulled him down into a kiss. This one was far slower and more loving, her lips slowly meshing against his like she was savouring it, a soft rumble rising from her throat as she kissed him. In an instant it connected in his mind, his cheeks rapidly darkening as he realised _why_ she was being so affectionate; why she was wearing such a skimpy outfit. She loved him – far more than she did anyone else.

He was stirred from his realisation as Tiamat broke off the kiss, shooting him a loving smile that confirmed his suspicions. She laid her hands over his and guided them towards her shoulders, her cheeks gaining a light pink tint as his fingers brushed against the straps of her pink apron. Ritsuka gulped, leaning down and initiating the kiss this time around; eliciting a pleased mewl from Tiamat.

''Aaaahh...'' Tiamat groaned approvingly as he grasped the straps, slowly tugging them off her smooth shoulders.

With her straps out of the way he could easily peel her pink apron down her front. He dragged out the kiss for as long as he could, intimately aware of how far he was pulling the apron down – feeling the gentle curve of her breasts as his hands ghosted over them. Only once his hands passed her boobs did he pull back from the kiss, staring down at Tiamat's gently-panting face before sliding his gaze down further.

Even though Tiamat rarely wore much clothing, seeing her bare breasts was a first for him – his cheeks blooming a dark scarlet as he stared at them. Large and round, tipped with pale pink nubs and visibly soft... they were beyond inviting. Tiamat sensed his hesitation and groaned affectionately, grasping his right hand and sliding it down to her breast, a low mewl passing her lips as his palm rubbed against her nipple.

''Tiamat-san...'' Ritsuka breathed, and gently squeezed her breast.

''Aahh~'' Tiamat let out a pleased groan, eyelashes fluttering as he tenderly groped her.

Ritsuka gulped and repeated the action, becoming aroused by the mere sight of Tiamat's blissful expression. His other hand slid down and joined its twin, both his hands slowly groping her soft breasts. They were so big there was no chance of fitting them in his hands, yet that hardly bothered him – if anything their large size only enamoured him, making him want to explore them fully.

Tiamat moaned as he gave her tits another slow squeeze, slowly shifting back until he was eye-level with her chest. Shoving down his embarrassment he leaned down until his breath brushed against her slowly-heaving breasts, shifting his hands down so he was cupping her large boobs – before he kissed her right breast. Immediately Tiamat let out a sensual groan, arching her back slightly and letting her eyes close, demonstrating the trust she had in him.

''Mm...'' Ritsuka hummed softly, planting an experimental kiss on her breast, smiling when she mewled. Compared to her prior monstrous appearance, seeing her so vulnerable and offering herself to him... it was adorable.

Shaking off his thoughts he refocused on her ample breasts, peppering them with kisses and relishing the heavenly softness. An idea hit him and he was unable to resist, burying his head between her boobs and kissing the delicate skin between them, smiling at the low groan that passed Tiamat's lips as he pleasured her.

Growing bolder he retreated from her breasts and instead went for her nipples, taking her right one into his mouth. Tiamat moaned as he started to suck on her soft nub, his tongue slowly circling around her pink nipple teasingly. After a few moments he swapped over to her other nipples, gently sucking on it as well and extracting soft moans from his busty companion, watching her writhe beneath him.

Ritsuka popped his lips off her nipple and took a moment to catch his breath, giving Tiamat the chance to act – a surprised grunt escaping him as she rolled them both over, reversing their positions. Immediately he found his face buried in her chest, but before he could act on it she shifted back a touch, enough that she could look him in the eye.

''Aaahh~'' Tiamat groaned lovingly, eyes all but glowing with affection.

He shifted back a bit at her silent gesture, his cheeks darkening as Tiamat wasted no time in going for his pants – swiftly unbuckling his belt and yanking his pants down. His boxers didn't last more than a few seconds before she tugged them down too, her eyes immediately locking onto his swiftly-hardening cock. The goddess' cheeks gained a cute red tint, demure embarrassment mixing with excitable happiness.

''Ahh~'' Tiamat softly groaned, before leaning in and planting a loving kiss on his cock.

Ritsuka shuddered and moaned, intimately feeling her soft lips against the tip before she trailed down, slowly peppering kisses down his length. Despite her clear inexperience she made up for it with pure love, tentatively exploring his cock with her lips; closely watching his expression as if hunting for his weak spots.

In response he slid a hand down and gently laid it on her head, stroking her hair. Tiamat groaned happily at his touch and doubled her efforts, lovingly kissing his cock all over. As if getting an idea Tiamat perked up – before slipping her tongue out and curling it around his shaft. Ritsuka gasped sharply at the lewd sensation, intimately feeling her wet tongue slithering over his shaft like a fleshy snake.

''Nn... g-good...'' Ritsuka moaned, stroking her head approvingly – smiling weakly at her happy groan.

Tiamat continued licking his cock for a little longer before she got curious, opening her mouth and gently wrapping her lips around his cock. Ritsuka let out a quiet groan at her cute curiosity, making Tiamat's lips quirk up into a smile before she sunk down further – the wet warmth of her mouth surrounding his cock. The goddess sunk halfway down before stopping, curiously lapping at his cock with her tongue for a few moments before rearing her head back.

A low, pleasure-filled moan passed his lips as Tiamat started bobbing her head; quickly finding a suitable rhythm. The goddess managed to sink further down his cock with each slow bob, occasionally tilting her head slightly as she sucked him off. A shudder ran through him and he slid his other hand down, both his hands gently curling around the base of her horns, gently pushing her down his dick.

''Aaah~'' Tiamat groaned warmly, her hot breath brushing over his cock.

The chaos goddess kept bobbing her head and sucking him off, growing more eager by the second until she was deep-throating him with ease. Her tongue lapped at the underside of his cock, stroking his length in tandem with her bobbing head; sending hot waves of pleasure along his shaft. Just as he began to twitch and throb in her mouth however Tiamat got an idea, perking up and pulling her lips off.

''Nn...'' Ritsuka shuddered as the wet warmth of her mouth abandoned his cock. ''Tiamat-san...?''

His confused murmur melted into a sharp gasp as Tiamat shifted closer – and promptly smothered his twitching cock between her breasts. The heavenly-soft, pillowy sensation was unlike anything he had ever felt before, gasping as she curiously slid her boobs up and down his length. Her crimson eyes flickered up to his, a smile gracing her features as she moved her breasts more eagerly, happy to pleasure him.

Tiamat continued bouncing her breasts, alternating between moving them up-and-down in unison to sliding one up while moving the other one down – the constant changes leaving him gasping for air. Tiamat clearly knew this, smiling warmly at him as she applying more pressure; smothering his throbbing cock between her warm breasts, unheeding of how much his dick was twitching.

Ritsuka grit his teeth, tipping his head back. ''T-Tiamat-san... I-I can't- _Nn!_ ''

The Master grunted sharply as she squished her breasts against his dick again, the sudden pressure pushing him over the edge – ropes of cum swiftly erupting from his cock and splattering up her collarbone. Tiamat moaned approvingly as he shot ropes of cum up her neck, several shorter ropes coating her ample breasts with his seed; much to her obvious delight.

''Aaaah...'' Tiamat groaned happily, squishing her boobs together and coaxing out every last drop of cum, smiling as it leaked down her chest.

Only when his orgasm subsided did Tiamat stop moving her breasts, leaning back slightly and gazing down at her chest curiously. To his embarrassment she trailed her fingers between her tips, scooping up some of his seed and popping the fingers into her mouth, tasting him – her face lighting up happily.

''Tiamat-san... don't do something... so embarrassing...'' Ritsuka breathlessly muttered, making the chaos goddess tilt her head in innocent confusion.

Her confusion swiftly melted into cute arousal a moment later, a happy smile curling at her lips. Without a word she crawled back up his frame until they were face-to-face, allowing her to lean in and kiss him full on the lips – a kiss that easily conveyed the genuine love she held for him. Ritsuka shuddered and returned the kiss, struggling to keep up with her honest passion in his breathless state.

Slowly his hands snaked down her sides and to her ass, gently groping her rear. Tiamat groaned approvingly into the kiss, gripping his shoulders tightly – before she rolled them over, leaving him on top of her. He didn't even question it, too busy kissing the goddess to mind; her lips becoming near-addictive with how soft and alluring they were.

When he broke off from the kiss and leaned back however, he only then noticed their compromising position – his sensitive, still-hard cock looming dangerously close to her pussy. As if confirming his thoughts Tiamat's hands shifted to his cheeks, making him look her in the eye and giving him a loving smile, her head dipping in a slight nod.

''Aah~'' Tiamat groaned softly, her bare legs gently stroking against his own.

Ritsuka blushed a deep red, quickly leaning down and kissing her again. Tiamat threw her arms around him and groaned into the kiss, her lips quirking up into a smile as she felt his erect cock press against her slick folds. Blindly he reached down and grasped his cock, rubbing it against her wet slit a few times until he got it right, finally sinking inside the chaos goddess.

''A-Aaah...'' Tiamat's grip on his cheeks tightened a touch, a brief flicker of pain shooting through her before it swiftly melted, becoming raw, hot pleasure.

''You okay...?'' Ritsuka asked worriedly, quickly retreating from the kiss.

The goddess merely smiled warmly at him and nodded, prompting him to hesitantly roll his hips again – pushing deeper inside her. Tiamat groaned softly as he buried his length inside her, a sound he unintentionally mimicked; groaning as her hot tightness squeezed his length. Each slow thrust made both of them groan and moan, and after a few thrusts he managed to fit most his length inside her womanhood, pausing for a brief few moments to catch his breath.

Tiamat wordlessly groaned at him, crimson eyes glowing with warmth. Ritsuka blushed at the sight and leaned down, kissing her again – this time a lighter, more affectionate kiss. Tiamat didn't mind; groaning lowly as he slowly rolled his hips and slid his cock in and out her pussy, the sensation of being filled melting her mind with ease.

''Aahhh...'' The chaos goddess groaned, tipping her head back as far as her horns would allow.

Seeing an opportunity Ritsuka wasted no time in attacking her neck with kisses, smiling at the sound of her throaty groan – her throat vibrating beneath his lips. His hands slid down to her sides as he starting thrusting in earnest, shuddering when she tightened around him in response. The sensation of her hot insides only made him thrust faster, his feeble resistance melting in the wake of how _good_ she felt.

At the sound of her sweet groans he moved faster, eagerly rolling his hips and plunging into Tiamat's pussy – her groans growing louder at his eagerness. He slowed for a brief moment as he leaned back, his hands shifting down to her hips before he resumed thrusting in earnest, his pelvis audibly slapping against hers as he bottomed out with each quick thrust.

''Aaah~!'' Tiamat groaned lustfully, arching her back as a sharp jolt of pleasure shot up her pelvis. ''Aaaaah!''

He shivered at her erotic groans, so much more arousing than her usual happy groans. Her ample breasts bounced about each time he slammed himself into her, his wild thrusting making her whole body jolt and shudder – but he didn't dare release her hips, lest he be forced to go slower. As if to remedy that Tiamat's right hand suddenly darted down to her own breast, groping it and causing her to let out a throaty groan, a cutely-lustful smile playing at her lips.

''Nn...'' Ritsuka swallowed, his cock throbbing from the sexy sight – a fact she seemed to realise, moaning deeply as she continued fondling her bouncing breast.

Tiamat's other hand remained above her, blindly gripping onto the bed in a weak, instinctual attempt to steady herself. Even so he didn't release her wide hips, continuing to pound into the naked goddess with every ounce of strength he could muster – the lewd sound of their skin smacking together echoing around the room, filling his ears with the erotic sound.

''T-Tiamat-san...'' He muttered out, groaning when her pussy clenched around his cock again – the heavenly tightness nearly causing him to blow right then and there.

Even without words Tiamat seemed to sense his building orgasm, her rosy cheeks turning a pretty scarlet. She let out an incoherent groan that conveyed her anticipation, her legs quickly wrapping around his waist and forcing his thrusts to become shorter but faster. The implication was not lost on him, his cheeks heating up as he realised Tiamat wanted him to cum inside – a notion confirmed when she smiled warmly at him.

Ritsuka groaned, pounding into the busty woman as fast as he could – eliciting a deep, throaty groan of delight from his partner as he stuffed her pussy full with his throbbing length. Her heaving breasts jiggled each time he bottomed out inside her, the wet smacking of their skin slapping together only fuelling his building orgasm. Tiamat's inner walls quivered and clenched around his cock repeatedly, her own orgasm clearly drawing near as he plunged into her passionately.

''A-Aaah~!'' Tiamat writhed, screwing her crimson eyes shut. ''A- _Aaahhh~!_ ''

Tiamat let out a sharp, throaty groan just as he bottomed out; her inner walls spasming around his length as she orgasmed.

Ritsuka gasped as she suddenly coiled tight around him, the ungodly hotness tipping him over the edge and sending his own orgasm rushing through him – before he too climaxed, unloading ropes of cum deep into the goddess, the sensation causing her to spasm in the throes of her orgasm.

''Aaah~'' Tiamat's hips buckled as he continued thrusting, unloading every last drop into her – a dazed smile curling at her lips. ''A-Aah...''

''Nn...'' Ritsuka shuddered at her cutely-blissful expression, rolling his hips a few more times until he came to a stop, his hips aching from moving so fast.

Silence fell upon them for a long minute, disturbed only by their heavy panting and soft groans as pleasure tickled their sensitive bodies. Slowly Tiamat slid her hands up his chest and around his neck, pulling his head down into her neck and letting her kiss him on the cheek.

''Aaah...'' Tiamat groaned softly, rolling her jaw for a moment – before she spoke. ''Aah... l-lovve... Maaasteeerrr...''

Ritsuka blushed deeply at her honest confession. ''I-I love you too, Tiamat-san...''

Tiamat's response was a happy kiss on the cheek, her legs snaking around him as she snuggled with him.

[END]

**Author's Note:**

> Tiamat's surprisingly cute, all things considered.
> 
> Also, completely unrelated note to my Azur Lane readers; I swear Hibiki's gonna be in the Dawning Ceremony event. I'm calling it now. I want it on record, she'll be there.


End file.
